ssh: don't start goroutines handling forwarded connections until needed
The extra goroutines were distracting while debugging something else,
especially as I wasn't using that feature. This also saves a bit of
memory.
Change-Id: Ia6489e64bbd3d5a6ff699a25018676d8ff8bd2e4
Reviewed-on: https://go-review.googlesource.com/112635
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>
diff --git a/ssh/client.go b/ssh/client.go
index 6fd1994..ae6ca77 100644
--- a/ssh/client.go
+++ b/ssh/client.go
@@ -19,6 +19,8 @@
type Client struct {
Conn
+ handleForwardsOnce sync.Once // guards calling (*Client).handleForwards
+
forwards forwardList // forwarded tcpip connections from the remote side
mu sync.Mutex
channelHandlers map[string]chan NewChannel
@@ -60,8 +62,6 @@
conn.Wait()
conn.forwards.closeAll()
}()
- go conn.forwards.handleChannels(conn.HandleChannelOpen("forwarded-tcpip"))
- go conn.forwards.handleChannels(conn.HandleChannelOpen("forwarded-streamlocal@openssh.com"))
return conn
}
diff --git a/ssh/tcpip.go b/ssh/tcpip.go
index acf1717..80d35f5 100644
--- a/ssh/tcpip.go
+++ b/ssh/tcpip.go
@@ -90,10 +90,19 @@
rport uint32
}
+// handleForwards starts goroutines handling forwarded connections.
+// It's called on first use by (*Client).ListenTCP to not launch
+// goroutines until needed.
+func (c *Client) handleForwards() {
+ go c.forwards.handleChannels(c.HandleChannelOpen("forwarded-tcpip"))
+ go c.forwards.handleChannels(c.HandleChannelOpen("forwarded-streamlocal@openssh.com"))
+}
+
// ListenTCP requests the remote peer open a listening socket
// on laddr. Incoming connections will be available by calling
// Accept on the returned net.Listener.
func (c *Client) ListenTCP(laddr *net.TCPAddr) (net.Listener, error) {
+ c.handleForwardsOnce.Do(c.handleForwards)
if laddr.Port == 0 && isBrokenOpenSSHVersion(string(c.ServerVersion())) {
return c.autoPortListenWorkaround(laddr)
}
